1. Field of the Invention
The present invention relates to a flexible multilayer thin film capacitor and an embedded printed circuit board using the same, and more particularly, a flexible multilayer thin film capacitor using a flexible metal substrate and an embedded printed circuit board using the same.
2. Description of the Related Art
Miniaturization, lightness, and high-functionalization of an electronic product, such as a smart phone and the like, are being actively ongoing. Due to the above trend, a multilayer ceramic capacitor (MLCC) is being developed as a multilayer thin film capacitor using a thin film manufacturing method. The multilayer thin film capacitor is mounted to a printed circuit board to be embedded therein. Hereinafter, a configuration thereof will be described with reference to the accompanying drawings.
As shown in FIG. 1, a multilayer thin film capacitor includes a silicon substrate 1, a dielectric thin film 2, an internal electrode thin film 3, a protecting layer 4, and an external electrode 5.
A plurality of dielectric thin films 2 and a plurality of internal electrode thin films 3 are alternately disposed on the silicon substrate 1, and a material of the silicon substrate 1 is formed of silicon Si. That this, the plurality of dielectric thin films 2 and the plurality of internal electrode thin films 3 are alternately disposed on the silicon substrate 1 to have a multilayer structure. The protecting layer 4 is formed on the dielectric thin film 2 that is positioned on an outside among the plurality of dielectric thin films 2 to protect the dielectric thin films 2 from an outside environment. The external electrode 5 is connected to contact with exposed intersections of the internal electrode thin films 3 alternately disposed on the substrate 1, to thereby configure a plurality of condenser circuits including the dielectric thin films 2 and the internal electrode thin films 3.
The conventional multilayer thin film capacitor may become thinned by manufacturing the dielectric thin film 2 and the internal electrode thin film as a thin film using the thin film manufacturing method, and may be embedded in a conductive inter-layer pad (not shown) of a printed circuit board (not shown) and thereby be mounted as a soldering 7 as shown in FIG. 2. When the printed circuit board is bent in a state where the multilayer thin film capacitor is embedded in the printed circuit board, a crack 6 may occur in a portion contacting with the soldering 7 since the silicon substrate 1 is applied. The crack 6 may cause a short phenomenon in which the plurality of internal electrode thin films 3 may be electrically connected.
The conventional multilayer thin film capacitor is formed of a material such as silicon. Therefore, when the printed circuit board is bent in a state where the multilayer thin film capacitor is embedded in the printed circuit board, a crack may occur in the multilayer thin film capacitor. Accordingly, there is a problem that a short of electrically connecting internal electrodes may occur due to the crack, thereby degrading the product reliability.